With the testing of Agency Power's STi turbo kit, they needed more fuel to overcome the factory 550cc injector limitation of 350 crank horsepower. With many STI owners wanting to push the limits of their STI, more fuel delivery is required. The Agency Power STI Injectors flow 816cc. These injectors are designed for cars with large turbo kits making 400+ horsepower. These injectors are available as a brand new set of 4. We recommend a larger fuel pump when paired with this injector upgrade to compensate for the fuel delivery needed.
Notes on Installation:
The likelihood of an injector sticking open is extremely low. However the design of the side feed fuel system can lead to a massive fuel leak into the motor past the lower o-ring if it is not completely seated down into the rail. It will seal on the top, but not on the bottom, allowing high pressure fuel to get past the bottom seal and directly into the motor. A slight nick in the o-ring, contamination from dirt falling into rail from injector removal without first cleaning the site, or even improper lubrication during installation can also cause leakage past the o-ring. It cannot be stressed enough to observe proper procedure during installation or seek professional installation if at all possible.
